Loss or deregulation of proteins involved in such diverse processes as cellular proliferation, cell cycle and Checkpoint control, DNA repair and cell death is a consistent feature of cancer cells. Cancer cells arise through a process of cellular evolution due to the accumulation of genetic changes. As cancers arise and progress, there is a selection for those genetic changes that give the cancer cell a proliferative advantage over normal eells. Because many cancers are not easily detected at early stages of development, nor readily curable using existing strategies, there is a need to identify new molecules that can be used both as diagnostic probes and as therapeutic targets. The Cellular Proliferation Research Program is organized around the theme that elucidating the web of connections between signal transduction pathways, cell cycle regulatory pathways and cell death pathways will help both to define origins of human cancer and to identify targets for the design of novel therapies and diagnostic tools. Research activities of members of this program focus on fundamental biological processes regulating cellular proliferation, including signal transduction, cell cycle and checkpoint control, telomere biology and apoptosis. These laboratories employ a diverse array of experimental approaches and model organisms including budding yeast, Drosophila melanogaster, Caenorhabditis elegans, Xenopus and mammalian systems. Investigators in the program have a strong record of collaboration and interaction with other Siteman Cancer Center members. Major goals of the program include: promoting collaboration and translation of new findings regarding basic biological processes into opportunities for understanding and treating cancer and to enhance the training environment at Washington University School of Medicine in the area of cancer through teaching, training and faculty recruitment. The Cellular Proliferation Research Program includes 29 members representing nine academic departments and one school. The Program is supported by $15,992,269 in funding, of which $2,918,008 is NCI funding and $11,690,123 is other peer reviewed funding. In the last grant period, members of the Cellular Proliferation Program published 433 manuscripts, of which 24.94% represented inter-programmatic, 4.15% represented intra-programmatic collaborations, and 2% ofthe inter-programmatic are also intraprogrammatic.